The present invention relates to a braking device particularly usable for skates including a shoe composed of a quarter articulated to a shell which is in turn associated with a frame for supporting one or more wheels.
In conventional roller skates, whether constituted by a shoe associated with a support for two pairs of mutually parallel wheels or by a shoe associated with a supporting frame for one or more aligned wheels, there is currently the problem of braking the wheels in order to adjust the speed of the skate.
It is known to use adapted pads or blocks, usually made of rubber, which are arranged at the toe or heel region of the shoe; when the user tilts the shoe forwards or backwards, the free end of the pads or blocks interacts with the ground and braking is thus achieved.
However, the operation of conventional brakes is not satisfactory because it requires the user to rotate the shoe, and thus the frame associated therewith, at the toe or at the heel, and this can cause the loss of balance with consequent fall.
U.S. Pat. No. 1,402,010 discloses a roller skate provided with a band which can be secured on the user's leg above the malleolar region and to which a rod is connected.
Said rod surrounds the leg to the rear and is then curved so as to laterally affect the leg until it is associated, at its ends, in the malleolar region, with a lever system which is articulated to a structure protruding from the wheel supporting frame.
The lever system protrudes to the rear of the frame and is connected to a plate which is shaped approximately complementarily to the curvature of part of an underlying facing wheel.
This solution is not free from drawbacks: first of all, a relative movement is produced between the band and the leg throughout sports practice, and this does not make its use comfortable due to the continuous rubbing of the band on the leg.
Furthermore, the plate is activated every time the user bends his leg backwards beyond a given angle, with no actual and easy possibility of varying this condition.
Furthermore, since the shape of the leg is different for each user, for the same rod length there is a different braking action at different rotation angles.
Furthermore, the rod rests and presses on the malleolar region, and this can cause discomfort or can cause accidental impacts.
Finally, the wheel wears out considerably.
U.S. Pat. No. 4,275,895 provides a partial solution to this drawback. This patent discloses a brake for skates provided with two pairs of mutually parallel wheels which acts at the rear wheels.
The brake is constituted by a flap which is associated with the shoe in a rearward region and with which a plate is associated in a rearward position. The plate is pivoted at the supporting frame of the shoe.
The plate has, at its free end, a transverse element on which a pair of C-shaped elements is formed at the lateral ends; following a backward rotation imparted to the flap, the C-shaped elements interact with the rear wheels facing them, in that they interact with the rolling surface of the wheels.
However, even this solution has drawbacks: it is in fact structurally complicated and therefore difficult to industrialize. It also entails the presence of adapted springs suitable to allow the flap to resume the position in which the pair of C-shaped elements does not interact with the wheels, thus further increasing structural complexity.
Furthermore, the structural configuration of the brake causes the pair of C-shaped elements to interact with the wheel even upon a minimal backward rotation imparted to the flap and therefore even for involuntary movements, and this creates unwanted braking actions and thus possible loss of balance or lack of coordination.
Finally, the interaction of the C-shaped element at the rolling surface of the wheels leads to rapid wear of the wheels and therefore to non-optimum rolling which necessarily entails continuous replacement of the wheels.
U.S. Pat. No. 4,300,781 discloses a braking device for skates which comprise pairs of mutually parallel wheels.
The brake is constituted by a plate which is pivoted transversely at the rear end of the frame for supporting a shoe. Blocks are associated with the ends of the plate and face the rolling surface of the pair of rear wheels.
The brake is activated by using a cable which is suitable to rotate the plate in contrast with a spring associated with the support for the pair of front wheels, so as to move the blocks into contact with the rolling surface of the pair of rear wheels.
The cable can be activated by means of rings or handles associated with a band which can be arranged on the legs of the user by virtue of the presence of temporary connection means.
However, this solution has considerable drawbacks: first of all, activation of the brake can lead to possible loss of balance because the user does not assume, with his body, a position suitable to control the sudden speed reduction; brake activation in fact involves only the skater's hand.
Furthermore, since the sport can be practiced while wearing trousers, when the rings are pulled the band may slip along the trousers or make them slide along the leg, hindering the braking action.
Furthermore, the loose cable is a hindrance to the skater and could accidentally catch during skating, especially since coordination of the arm-legs movement rhythmically moves the legs laterally outwards.